Dishwashing machine having automatic inlet control



June 15, 1948. 5 ,l =rr w s 2,443,414

DISH WASHING MACHINE HAVING AUTOMATIC INLET CONTROL Filed March 29, 1946 2 Sheets-Sheet 1 .f g y 7.

June 1948- s. G. BURT-WELLS 2,443,414

DISH WASHING MACHINE HAVING AUTOMATIC INLET CONTROL Filed March 29. 1946 2 Sheets-Sheet 2 Irnnfon Patented June 15, 1948 UNITED sTATEsg PATENT OFFICE DISHVVASHINGL CHINE HAVING AUTO- MA ET CONTROL TIC Sidney G.

assignor to Burt-Wells, Toronto, Ontario, Canada,

Triumph Dishwashers Limited.

This invention relates to improvements in dish washing machines of the typein which the dishes aresupported in racks in an enclosing cabinet and water is sprayed over the racks and also protected upwardly in a spray from a sump by a motor-driven impeller and the principal object of the invention is to obviate the possibility of flooding the machine with water in the event of the electric motive power being cut oil! or the 1ailure oi the drive mechanism while the machine is in operation.

A further object is to ensure the evacuation oi the water from the washing compartment prior to the introduction of a further supply of fresh water.

The principal feature or the invention consists in the novel arrangement of a fluid controlled mechanism connected with a pressure pump operated by the driving motor of the machine which maintains the pressure water supply control mechanism in operative relation while the motor is operating and automatically effects the shutting off of the water supply in the event or the motor drive ceasing to function.

A further important ieature of the invention consists in the novel construction and arrangement of means for timing the operation or the pressure water feed to the washing compartment and the release or draining of the water therefrom.

In the accompanying drawings Figure 1 is a plan view of the mechanism for controlling the flow oi. water to and from the washing compartment.

Figure 2 is an end elevational view of the control mechanism.

Figure 3 is a detail elevational view of the 2 The present invention is adapted for application toa dish washing machine in which a washing compartment arranged within a suitable cabinet i is provided with a sump 2 in which a rotary impeller operates 0 direct water upwardly from the sump to efiect the cleansing of the dishes and suitable spray devicesare arranged to direct water over the dishes and to supply the washing water to the sump.

Below the sump 2 and within the bottom of the cabinet is arranged a gear box 8 operatively connected to a motor 4. A shaft 8 extends vertically upward from the gear box and enters the bottom of the sump through a suitable packing gland to rotate the washing impeller.

A circulating gear pump 8 is mounted on the gear box 3 and drawing oil from the interior control mechanism showing the hydraulic governor in section and in position for permitting the mechanical operation of the valve for feed- .ing water to the washing compartment,

Figure 4 is an elevational part sectional view similar to Figure 3 showing the hydraulic governor and its associated mechanism in the inoperative position.

Figure 5 is a view similar to Figure 3 showin the cam for opening the drain valve in the position to open such valve. 1

Figure 6 is a plan detail of the cam mechanism for operating the water control valves and the electric cut-out for stopping the motor on the completion of a cycle.

Figure 7 is a sectional view of thedrain valve in the closed position.

Figure 8 is a wiring diagram.

of the gear box forces same through a pipe 1 leading to the base of a vertically arranged cylinder 8.

An outlet port 9 is arranged in the side wall of the cylinder 8 a short distance above the bottom. 4

Within the cylinder 8 is arranged a loaded piston Ill which is adapted to be lifted by the pressure of the oil flowing from the pump until the bottom of the piston clears the port 9 and allows the pressure oil to how from the cylinder through a pipe ll back to the gear box, the constant flow of oil while the pump is working, holding the piston in a raised position. When the pump ceases to operate the loaded piston returns to the bottom of the cylinder forcing the oil below the port 9 back through the pump. h

, A shaft i2 extending from the gear box 3 on the side adjacent to the pump 8 and the cylinder 8 is operatively connected through suitable gears to the'motor to operate at a slow speed and the outer end of the shaft is journalled in a standard IS.

A pair of parallelly spaced plates H are rigidly supported from one end in a vertical position from the top of the cylinder 8, as shown in Figures 1 and 2, said plates extending above the shaft i2.

Angle iron brackets i5 are secured to the outward sides of the plates l4 and to these brackets are secured a vertical cross plate [6 to which are secured at either vertical side by suitable brackets the plates I! which are of an inverted L-shape and extend downwardly to the base I8 of the cabinet where they are rigidly secured.

3 20. the bottom fitting of which is connected by a pipe 2| to a hot water supply tank 22 which is fitted with a suitable form of electric heater 23 7 controlled by a suitable thermostat 24.

valve 20 is of a spring and pressure closed typefiand is provided with an extension stem 25 which when pressed inwardly opens the valveallowing the water from the tank to flow therethrough to a pipe 25 which is connected to the spray devices within 'the washing compartment (not shown).

A bell crank lever 21 is pivotally mounted on a pin 28 extending between the parallelly arranged plates and carries a threaded pin 29 secured by lock nuts 30, which pin is adapted to engage the stem 25 of the valve 20.

The piston i is provided with a vertical extension stud 3I which extends above the cylinder between the plates i4 and to the upper end of this stud is pivotally connected an arm 32 which is connected at a point intermediate of its length by a link as to the end of the belllcrank 21.

The free end of the arm 32 is provided with a roller 34 which is adapted to engage the periphery of a cam disc 35 mounted on the slow moving shaft [2.

The cam disc 35 is provided with a pair of radial cam plates 35 and 31 arranged diametrically opposite and extending beyond the periphery of the disc 35 so that as they engage the roller 34 when the piston I0 is in the raised position, as shown in Figure 3, the pin 29 of the bell crank will engage the valve stem 25 and open the valve.

If however the piston I0 is in the lowered position the cams 36 and 31 will not move the bell crank lever to engage the valve stem to open the valve, as is illustrated in Figure 4.

This device provides a safety element which will obviate the flooding of the machine, as the water inlet valve cannot be opened when the motor is not running and the pump operating to lift the piston Hi so that the bell crank 21 will, be in a position to be operated to open the inletvalve and if the motor fails while the inlet valve is open the piston drops and pulls the bell crank 21 away from the inlet valve stem and the valve closes automatically.

Connected to the bottom of the sump 2 is an outlet pipe 38 in which is arranged an outlet valve 33 which is held closed by a spring 40. The stem 4| of the valve 39 is operatively connected by a link 42 to a lever 43, which lever is mounted on one end of a horizontal shaft 44 supported at one end in a bearing block 45 and at the other end in a bearing in the vertical plates ll supporting the inlet valve.

A lever arm 45 is secured to the shaft 44 and extends inwardly and is provided with a roller 41 which engages the periphery of a cam disc 48 mounted on the slow moving shaft I2 adjacent to the cam disc 35.

The cam disc 43 is provided with a pair of radially extending cam plates 49 and 50 which are arranged diametrically opposite. The lever arm 46 is preferably held with its-roller in engagement with the cam disc by a spring 5| connected to one of the plates IT.

The cam plates 49 and 50 are so arranged that as the shaft 12 rotates each of these cams will engage the arm 46 and open the outlet valve to drain the water from the sump before the cam plates 35 or 31 operate to open the water inlet valve.

In the wiring arrangement as illustrated in Figure 8 a starter switch A is arranged in the power supply lead to the water heater 23, the. "thermostat 24 for controlling the heat of the water in the tank 22 and the motor 4 and in this circuit is arranged a micro switch D. Y

The switch D is provided with a spring arm 52 which engages the periphery of a disc 53 mounted on the slow shaft 12. This disc engaging the spring arm 52 maintains the switch D closed until at the completion of .a cycle of operation of the washer the disc 53 turns to a position where a notch 54 therein permits the arm52 to spring outwardly to efiect the opening of the microswitch and the interruption of the power circuit to the motor and other electrically operated elements of the washer. y

In the operation of a dish washer equipped with a device as herein described, the electric current maintains the water in the supply tank 22 at a desired temperature controlled by the thermostat. The motor having stopped on a previous operation immediately after the evacuation of the water from the machine, the drain valve operating lever arm is resting on the circular periphery of' the cam disc 48 behind one of the cam plates 49 or 50.

The water inlet valve operating arm 32 is resting on the circular periphery of the cam disc 35 in front of one of the cam plates 35 or 31.

On the closing of the starter switch current flows to the motor 4 by-passing the micro-switch D and the motor starts the shaft i2 and cuts in the micro-switch.

The pump 5 forces oil into the cylinder 8 lifting the piston l0 against the loading of the spring [0' and raises the arm 32 at its outer end. The cam plate adjacent the roller end of the arm 32 raises the arm and tilts the bell crank 21 to open the inlet valve 20 allowing water to flow to pipe 26 and the sprays in the washing compartment. The cam plate maintains the flow of water for a brief period sufficient to direct the required amount of water into the machine for a washing and the cam plate then drops the arm allowing the valve 20 to close.

The water flows over the dishes and is deposited in the sump from where it is projected upward by the impeller operatively connected to the shaft 5.

After a predetermined period one of the cam plates 49 or 50 operates the lever arm 46 to open the drain valve and holds it open a sufilcient length of time to evacuate the washing water, then allows the arm to drop, and the valve to close.

The second cam plate 36 or 31 then opens the inlet valve for a suflicient length of time to rinse the washed dishes and immediately after the closing of the inlet valve the cam plate 49 or 50 opens the drain valve to let the rinse water out.

Immediately following the closing of the drain valve following the rinse, the disc 53 carried by shaft l2 moves to open the micro-switch as described and the cycle is completed with the machine reset and ready for a repeat operation. v

It will be understood that the sump is drained after each operation of the inlet valve; that the inlet valve cannot open unless the motor is running and the oil pump is functioning and if pump or motor fails the inlet valve automatically closes.

What I claim as my invention is:

1. In a dish washing machine, th combination with a dish washing compartment having a water inlet and an electric motor operated water impeller operating in a sump below saidinlet, a

hot water supply, a water inlet valve connected between said supply and said water inlet, a drain valve leading from the sump, of means for opening the inlet valve, fluid pressure operated means for holding said inlet valve opening means in operative position, means operated by said motor for supplying the pressure fluid for holding the inlet valve opening means in operative position, means operated by,said motor for operating said inlet valve opening means for briefly opening the inlet valve, and means operated by said motor for operating the drain valve.

2. In a dish washing machine, the combination with a dish washing compartment having water inlet sprays and an electric motor operated water impeller operating in a sump below said sprays, a hot water supply, a water inlet valve connected between said supply and said inlet sprays, a drain valve leading from the sump, of a fluid pump operated by said motor, a cylinder connected at the bottom with the discharge from said pump, a discharge arranged intermediate of the height of said cylinder, a piston in said cylinder, a lever adapted to engage and open said inlet valve operatively connected with said piston, and means operated by said motor for operating said lever to open the inlet valve when the piston is in the raised position through the operation of said D p.

3. In a dish washing machine, the combination with a dish washing compartment having a water inlet and an electric motor operated water impeller operating in a sump below said inlet, a self-closing water inlet valve arranged between said water supply and said inlet, and a selfclosing drain valve leading from said sump, of a reduction gear connected withsaid motor, a shaft extending from said reduction gear, a cam disc mounted on said shaft having diametrically -opposed cam plates thereon, a floating lever mechanism adapted to operatively engage said cam plates to open said inlet valve, hydraulic means for holding said floating. lever mechanism in position to operate said inlet valve when operated by said cam plates, a cam disc mounted on said shaft having diametrically opposed cam plates thereon, and lever means engaging the cam plates on the latter cam disc to open the drain valve.

4. A mechanism as claimed in claim 3 in which the drain valve operating cam plates are arranged to openthe drain valve then effect the closing thereof immediately prior to the opening of the inlet valve.

5. In a dish washing machine, the combination with a dish washing compartment having water inlet sprays and an electric motor operated water impeller operating in a sump, a self-closing water inlet valve arranged between said water supply and said sprays, a self-closing drain valve leading from said sump, of a reduction gear connected with said motor, a shaft extending from said reduction gear, a cam disc mounted on said shaft having diametrically opposed cam plates thereon, a bell crank lever mounted on a fixed pivot and adapted to engage and operate said inlet valve to open, a link connected to said bell crank, an arm pivotally mounted and connected intermediate of its length to said link said arm engaging said cam disc and being operated by the cam plates thereon, means governed by the operation of said motor for moving the pivotal mounting of said arm into or out of operating position to open said inlet valve, and means operatively connected with said shaft for operating said drain valve.

6. In a dish washing machine, the combination with a dish washing compartment having a water inlet and an electric motor operated water impeller operating in a sump, a hot water supply, a water inlet valve arranged between said supply and said inlet, a drain valve leading from the sump, of a gear box arranged below said sump having an impeller shaft extending upwardly into said sump and operating said impeller, a slow moving shaft extending horizontally from said gear box, a pair of cam discs mounted on said horizontal shaft, cam plates diametrically arranged on one of said discs to operate the inlet valve, cam plates diametrically arranged on the other of said discs and arranged to lead the aforesaid cam plates, means operated by the leading cam plates for operating the drain, valve, means operated by the lagging cam plates for effecting the operation of the inlet valve, and means interposed in the inlet valve operating means for ensuring the closing of the water inlet valve on the stopping of the motor.

7. A device is claimed in claim 1 in which means are provided to automatically stop said motor after a predetermined cycle of operation of said inlet and outlet valves.

SIDNEY G. BURT-WELLS.

REFERENCES orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS 

